Conventionally, in a process of manufacturing various kinds of workpiece, such as a bearing ring (inner ring, outer ring), grinding on an inner diameter portion of a workpiece (e.g., inner ring) or grinding on a raceway groove of another workpiece (e.g., outer ring) is performed. Various proposals have been made in connection with such a grinding technique (see, e.g., Patent Document 1).
According to a conventional grinding technique, when setting a positional relationship between a grinding wheel and a workpiece at the time of, for example, switching workpiece settings, the workpiece is set on a spindle, and then a teaching operation is performed in which an infeed shaft is manually operated to bring the grinding wheel provided on the infeed shaft into contact with the workpiece. For example, the teaching operation with respect to the inner ring includes a manual operation of the infeed shaft to a position where the grinding wheel abuts (contacts) an inner diameter surface of the inner ring. Further, the teaching operation with respect to the outer ring includes a manual operation of the infeed shaft to a position where the grinding wheel abuts (contacts) the raceway groove of the outer ring.